Two-cycle engine



March 31, 1942. c. A; TOCE EI'AL TWO-CYCLE ENGINE Filed Aug. 23, 1941 5Sheets-Sheet 1 GHARLEs ATocE V\c'roR J1 TocE INVENTORAS. m (1% March 31,1942. c. A. TOCE ETAL 2,278,038

Two-CYCLE ENGINE Filed Aug. 23, 1941 I5 Sheets-Sheet 2 CHARLES ATQVICTOR J. TocE Om ATTORNEY.

C. A. TOCE ET AL A March 31, 1942.

TWO-CYCLE ENGINE Filed Aug. 25, 1941 5 Sheets-Sheet 5 i .5. CHARLES ATone V1C TOR 3. Tom? INVENTORfi 5MB. 00am.

Patented Mar. 31, 1942 STATES PATEF OFFIC' insure i 'Giainis.

The invention relates to a two-cycle internal combustion engine of thepro-compression type and specifically includes. an arrangement wherebycompressed air is fed into the cylinder to scav enge the cylinder andthe fuel thereafter injected into the combustion chamber.

With two-cycle internal combustion engines various arrangements havebeen provided heretofore for pie-compressing the explosive mixture and.for scavenging the cylinders. Considerable dificulty has beenencountered in these prior devices, however, because if the gaseousmixture forced into the combustion cylinder under pressure is to effecta complete scavenging of the combustion gases, it seems obvious that apercentage of the incoming explosive mixture will pass on through theexhaust opening with the combustion gases, so that there has beendifficulty in designing an engine whereby satisfactory scavenging couldbe obtained on the one hand and the economical use of fuel on the otherhand.

' The present invention contemplates a solution of this problem bypro-compressing air from the atmosphere and using this air as ascavenging medium and after this scavenging operation has been completedand a body of this compressed air trapped in the combustion chamber,then the fuel is injected-and the explosion promoted. In this manner itis not imperative that the arrangement of the engine be such that therebe no escape of the incoming compressed air through the exhaust port,but as a matter of fact, some of the incoming air may pass out theexhaust port in order to obtain a satisfactory scav eng'mg of thecylinder.

'It is, therefore, one of the objects of the intary valve in two-cycleinternal combustion engines.

' Still another objector the invention is to provide a combinationpiston and compression unit wherein the piston operates in thecombustion Fig. 5. In Fig. 1 the body of the engine is illustrated at 2and may be of any desired type of construc-' tion which is arrangedto-support a crankshaft 3.

1 vention to pre-compress air and use it in scavchamber and acompression head operates pre-compression chamber.

Still another object of the invention is to provide a rigid assemblywherein a piston and compression head are in axial alignment.

Still another object of the inventionis to arrange a two-cycle internalcombustion engine with compression and combustion chambers on oppositesides of a crankshaft.

Still another object of the invention is to provide a bypass forpre-compressed air from the compression chamber to the combustionchamber of a'two-cycle internal combustion engine.

Other and further objects of the invention will be readily apparent whenthe following description is considered in connection with theaccompanying drawings wherein:

Fig. 1 is a longitudinal section through an em gine constructed inaccordance with the invention and showingcertain, parts in elevation.

ina

Figs. 2 and 3 are sections taken on the line.

2-2 and 3-3, respectively, of Fig. 1.

Fig. 4 is a section taken. on the line 6- 3 of Fig. 1.

Fig. 5 is a vertical sectional view of the piston and compression unit.

Fig. 6 is a section taken on the line. 5-5 of by means of the pluralityof sets of bearings such as 4. The present form shows a two-cylinderengine wherein the crankshaft has the throw portions 5 arranged toreceive the connecting rod 8 of each cylinder. the body is arranged witha compression cylin der 9, which is best seen in Fig. 2, as having aport iii controlled by the rotary valve H. inlet 12 into the valve isshown as being opened while the head moves up to permit the inlet of airto the chamber 9. The outlet i3 from the compression chamber isconnected to the conduit l4 which is, in turn, connected into thecombustion cylinder l5.

' The valve ll may be driven by the valve shaft l6 from the 'gear trainI! which is, in turn, driven by the gear "on the crankshaft 3. Suitableantifriction bearings and the usual cormectiorrslfor such gearing havebeen provided.

The combustion cylinder l5, as seen in Fig. 2,

has the bypass ll arranged partway along the cylinder so as to providefor the inlet of compressed air. The exhaust or outlet 20 is shown asbeing on the opposite side from the inlet but The base portion 8 of itmay be arranged otherwise if desired. The

head of this cylinder contains openings II which may receive spark orignition plugs, and the openings '22 may contain suitable injectors forl fuel.

. The piston and compression unit is seen in side elevation in Fig. 2and in section in Fig. 5 wherein the piston has the wrist pin openings26 to receive the wrist pin 21' carried by the connecting rod C.

The piston 25 is of the barrel type and has a particular construction inthe form of a supporting rib 21 adjacent the lower end of the piston.

-This rib has the bosses 2s thereon, which are seen in Fig. 6 as beingfour in number. These bosses each receives a'rod 30 which may be rigidlyconnected in the boss in any desired manner. These rods are spacedcircumferentially around the piston on quarter points, as-seen in Fig.6, with a view of straddling the crankshaft thethro'w 5 of the crank andits counter-weight 1 in a transverse direction. In other words, theserods straddle the crankshaft and support the compression head 3| ontheir lower ends.

The compression head 3| is in the form of ashort piston which isarranged to reciprocate in I the compression cylinder 9. In this mannerthe combustion cylinder and the compression cylinder are diametricalwith regard to the crankshaft; as is readily apparent from Fig. 2. ThisAs the piston reverses its stroke and closes the inlet and outletvalves, there will be a body of compressed air trapped in the combustioncylinder. The piston moves up to efiect further compression of this air.At a suitable period in this operation, the desired amount of fuel willbe inj ected into the compressed air so as to obtain an explosivemixture. The ignition of this mixture will occur at the proper time toeffect the explo- 3 in one direction and allowing the operation of 3tends to deflect the incoming compressed air and cause Y it to circulatein the combustion chamber, while the opposite face allows the opening ofthe exhaust port 20 as the piston moves down. In this manner completescavenging of the combustion cylinder is obtained because the ports andthe piston can be so constructed and arranged that the amount ofcompressed air to be fed into the cylinder will be sufllcient to obtaincomplete scaven ing of the combustion gases.

This is true because the exhausting of some of the compressed air alongwith the combustion gases will not affect the economy of the engine asregards fuel.

The righthand side of Fig. 1 shows the usual mechanism for injection ofthe fuel and operation of the electric systems which are well known withinternal combustion engines and need not be here described in detail.

In operation, as the piston moves down to uncover the inlet connectionN, there will be an inflow of compressed air from the compression -sionand power stroke of the engine.

During this upstroke operation the valve II will open, as seen in Fig.2, to permit the inlet of air to the compression chamber, and this valvewill close on the downstroke so that the air in the chamber 9 and thebypass M will be compressed. The valve II is of such width that theinlet I2 and outlet M will never be interconnected.

Broadly, the invention contemplates a two-.

rods connecting'said piston and head in axial alignment.

2. A combination piston and compression unit for engines including apiston, a compression head, and a plurality of rigid rods connectingsaid piston and head in axial alignment, said rods being spaced toprovide for the operation 'of a connecting rod and crankshafttherebetween.

3. A multicylinder two-cycle internal combustion engine including abody, a crankshaft therein, a set of axially disposed cylinders onopposite sides of said crankshaft, one of each set being a combustioncylinder, another of each set being a compression cylinder, a piston andcompression unit extending about said crankshaft and having a piston forsaid combustion cylinder and a head for said compression cylinder, arotary valve to control the inflow and outflow of air relative to saidcompression chamber, means connected to conduct the outflow to saidcombustion chamber, and additional means to inject. fuel into saidcombustion chamber.

4. A multicylinder two-cycle internal combustionengine including a body,a crankshaft therein, a set of axially disposed cylinders on oppositesides of said crankshaft, one of each set being a. combustion cylinder,another of each set being a compression'cylinder, a piston andcompression unit extending about said crankshaft and having a piston forsaid combustion cylinder and ahead for said compression cylinder, arotary valve to 7 control the inflow and outflow of air relative to saidcompression chamber, means connected to conduct the outflow to saidcombustion chamber, and additional means to inject fuel into saidcombustion chamber, said combustion chamber being scavenged by theinflow of air prior to the injection of fuel.

CHARLES A. TOCE. VICTOR J. TOCE.

